Just when you thought it was safe to buy Boeing stock... because, hell, what more could go wrong? Well, this...
Late last week we warned of this weekend's 'Y2K'-moment for GPS systems. Here’s what’s going on...
The rollover issue itself is caused by the fact that GPS systems count weeks using a ten-bit parameter. This means they start counting at week zero and reset when they hit week 1,024.
The first count (or “GPS epoch”) started on January 6th, 1980, and the first reset took place on August 21st, 1999. That means the next one is due April 6th this year. (source)
Some experts thought that the risk is negligible, while others thought this is something to which we should pay strict attention.
Carl “Bear” Bussjaeger, a New Hampshire-based science-fiction writer, Air Force veteran and former telecommunications network technician, reached out to us via Twitter to say that the link between GPS timing and telecom networks is not direct.
“Networks don’t time off GPS,” Bussjaeger said in a tweet. “They time off internal/master station clocks. Those clocks periodically synchronize off GPS.”
In a further conversation, Bussjaeger told us he had monitored the 1999 GPS epoch rollover as part of his telecoms job, and that there was “not so much as a bit error” on the network clocks.
“The clocks used in telecoms can free-run for days,” he said. “They’re very stable. GPS timing is really just a backup to the backup.”
During an epoch rollover, Bussjaeger said, “geolocation could glitch, but only momentarily, if at all. A GPS unit might have to reacquire the birds [satellites] to determine its location, but it’s no worse than turning on a unit and waiting for it to acquire [the satellite signal] in the first place.”
“Twenty years ago, we didn’t have a problem,” he added. “I rather expect that clocks are better, more stable now.” (source)
And rightly, not everyone sees it as a non-event.
“I would say it’s legitimate to be concerned,” Brad Parkinson, the retired Air Force colonel and Stanford University professor who was the lead architect of GPS, told San Francisco’s KPIX-TVin an interview published April 2.
“GPS affects everything we do,” he said. “It affects timing, banking, cell towers, airplanes, ships, passengers in cars … everything that we can imagine.”
“If you’re driving your car and it were to suddenly say you’re in the middle of the Pacific Ocean, be very suspicious,” he told KPIX-TV. (source)
So, basically, the vibe we got from this is that nobody really knew what will happen, or even if anything will happen.
Well, now we know, something has happened.
China Aviation Review reports that: "Multiple Boeing 787s in China experienced GPS 20 years rollover issue. Some aircrafts have to be grounded waiting for an update."
Multiple Boeing 787s in China experienced GPS 20 years rollover issue. Some aircrafts have to be grounded waiting for an update. pic.twitter.com/IEFF2GHIt2— ChinaAviationReview (@ChinaAvReview) April 7, 2019
And in a follow-up tweet confirming that "Currently about 15 787s were affected in China."